1. Field of the Invention The present invention relates to polyamide compositions, more particularly to compositions and processes which are related to chain extended polyamide compositions.
2. Description of the Prior Art
Polyamide compositions find widespread use due to one or more desirable properties, i.e., toughness, rigidity, chemical resistance, and the like. However, the use of various types of polyamides is sometimes limited due to inadequacies in molecular weight and/or molecular weight distribution. For example, low molecular weight polyamides are unsuitable for use in blow molding operations which require that the composition have a high melt viscosity so to allow blow molding of the parison into an article. To overcome such shortcomings, it is known to the art that the use of a plurality of additives, in particular various reactive compositions may be used in conjunction with the one or more polyamides of a composition in order to increase the molecular weight thereof.
EP Published Application 0 232 878 teaches polyamide compositions which include a polyamide composition and a reaction product of ethylene and a polymerizable carboxylic acid group containing compound, and optional copolymerizable monomer.
EP Published Application 0 232 879 teaches polyamide compositions which contain in addition to the polyamide an ethylene copolymer, a copolymer product of a vinyl aromatic monomer and a polymerizable carboxylic acid containing monomer and a homopolymer or copolymer containing a conjugated diene.
As may be seen from the prior art, and the activity therein, there remains a need for continued development, and further improved compositions comprising polyamides which may be produced to have desired molecular weight characteristics to make them suitable for use in a variety of production processes, particularly in extrusion and blow molding techniques. It is to this need, as well as other needs, that the present invention is addressed.